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What is a SIP Trunk?

A SIP Trunk is an alternative to a traditional phone line or ISDN line for connecting on-premises phone systems or PBXs. They use the internet to route calls to the Public Switched Network. Businesses are benefiting from replacing traditional phone lines with SIP Trunks. Broadly these benefits are:

  1. Cost Savings
  2. More flexibility and control over call routing
  3. NBN readiness
  4. Ability to take phone numbers out of local area exchanges
  5. Smarter phone features and unified communication

When should a business choose SIP Trunks instead of a hosted phone system like Commander Phone?

A business should look into purchasing SIP Trunks when they decide that their needs are best met with a premise-based phone system. This system is often referred to as a PBX or IP-PBX. Commander Phone is an alternative to a premise based phone system where the phone system resides in the cloud and is fully hosted and maintained by Vocus. Commander Phone is charged on a per month per handset basis compared with premise based phone systems that are typically purchased through high capital outlay with the addition of monthly SIP Trunking costs.

What equipment do I need for my SIP Trunk?

Your phone system needs to be SIP or IP ready (an IP-PBX). Traditional or Non SIP ready phone systems can also be made to work with SIP Trunks via a voice gateway or IAD (Integrated Access Device). The gateway provides an interface between your phone system and your SIP trunks translating the information passed through it.

In addition your SIP trunks use your data or Internet service to carry phone calls and other related signals. You will need a suitable data service to use your SIP Trunks.

Will I need to upgrade my Internet or data service?

SIP Trunks are delivered over an Internet or data service. You may wish to upgrade your data service depending on the number of simultaneous calls or channels purchased for your SIP Trunk, and the amount of other Internet data usage. When SIP Trunks are not being used, the bandwidth otherwise allocated to them is freed up to be used for other applications, such as email and general web use. This is another benefit of SIP Trunks over traditional phone lines. Alternatively you may consider a dedicated data service for your SIP Trunks.

Do I have to purchase SIP Trunks in groups of 2 or 10 like ISDN lines?

No – Vocus allows you to purchase Smart SIP services in single channels after a minimum of 2 channels (or 5 Channels for SIP Plus PRI) is purchased. This allows further cost savings instead of being forced to pay for lines or channels that you do not need and will not use.

Can I take my existing numbers with me when I relocate?

A great feature of Vocus SIP Trunks is the ability to support business relocations by enabling a geographic number to be retained, without incurring any ongoing call forwarding or exchange based diversion costs. This not only ensures a consistent customer experience, it also reduces the cost impact associated with having to change company stationery, directory entries and advertisements. We can also supply our SIP trunking customers with out-of-area geographic number ranges for customers, who for example wish to appear local, even if they don’t have a local physical presence.

Can I transfer my existing phone numbers to Vocus Smart SIP?

Yes. At your request, we can transfer your existing business numbers to your Commander SIP Trunks. This is called a number port and can be done once your SIP Trunks are installed and are operational. We can also transfer your existing phone numbers even if you are moving outside your local calling zone without incurring any ongoing call forwarding or exchange based diversion costs.

Can I manage my SIP Trunks myself?

Yes. Commander Smart SIP comes with Command Central our online self-management portal so you can make changes anytime from anywhere on any internet enabled device.

Can I keep my existing PBX?

Yes – In most cases Vocus will be able to provide a SIP Trunking solution for your existing PBX. Vocus Smart SIP can extend the life of your existing phone system by providing additional functionality that may not be provided by older phone systems. It also allows you to transition to a hosted phone system like Commander Phone at your own pace if you wish to.

Vocus Smart SIP has been tested and is supported with the phone systems provided through our Commander Centres. Our SIP Trunking platform is the platform of choice for many companies worldwide connecting many other brands of phone systems.

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